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  • only in /asuswrt-rt-n18u-9.0.0.4.380.2695/release/src-rt-6.x.4708/linux/linux-2.6/arch/cris/arch-v32/kernel/
1#include <linux/types.h>
2#include <asm/delay.h>
3#include <irq.h>
4#include <hwregs/intr_vect.h>
5#include <hwregs/intr_vect_defs.h>
6#include <asm/tlbflush.h>
7#include <asm/mmu_context.h>
8#include <hwregs/asm/mmu_defs_asm.h>
9#include <hwregs/supp_reg.h>
10#include <asm/atomic.h>
11
12#include <linux/err.h>
13#include <linux/init.h>
14#include <linux/timex.h>
15#include <linux/sched.h>
16#include <linux/kernel.h>
17#include <linux/cpumask.h>
18#include <linux/interrupt.h>
19#include <linux/module.h>
20
21#define IPI_SCHEDULE 1
22#define IPI_CALL 2
23#define IPI_FLUSH_TLB 4
24#define IPI_BOOT 8
25
26#define FLUSH_ALL (void*)0xffffffff
27
28/* Vector of locks used for various atomic operations */
29spinlock_t cris_atomic_locks[] = { [0 ... LOCK_COUNT - 1] = SPIN_LOCK_UNLOCKED};
30
31/* CPU masks */
32cpumask_t phys_cpu_present_map = CPU_MASK_NONE;
33EXPORT_SYMBOL(phys_cpu_present_map);
34
35/* Variables used during SMP boot */
36volatile int cpu_now_booting = 0;
37volatile struct thread_info *smp_init_current_idle_thread;
38
39/* Variables used during IPI */
40static DEFINE_SPINLOCK(call_lock);
41static DEFINE_SPINLOCK(tlbstate_lock);
42
43struct call_data_struct {
44	void (*func) (void *info);
45	void *info;
46	int wait;
47};
48
49static struct call_data_struct * call_data;
50
51static struct mm_struct* flush_mm;
52static struct vm_area_struct* flush_vma;
53static unsigned long flush_addr;
54
55/* Mode registers */
56static unsigned long irq_regs[NR_CPUS] = {
57  regi_irq,
58  regi_irq2
59};
60
61static irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id);
62static int send_ipi(int vector, int wait, cpumask_t cpu_mask);
63static struct irqaction irq_ipi  = {
64	.handler = crisv32_ipi_interrupt,
65	.flags = IRQF_DISABLED,
66	.name = "ipi",
67};
68
69extern void cris_mmu_init(void);
70extern void cris_timer_init(void);
71
72/* SMP initialization */
73void __init smp_prepare_cpus(unsigned int max_cpus)
74{
75	int i;
76
77	/* From now on we can expect IPIs so set them up */
78	setup_irq(IPI_INTR_VECT, &irq_ipi);
79
80	/* Mark all possible CPUs as present */
81	for (i = 0; i < max_cpus; i++)
82	    cpu_set(i, phys_cpu_present_map);
83}
84
85void __devinit smp_prepare_boot_cpu(void)
86{
87	/* PGD pointer has moved after per_cpu initialization so
88	 * update the MMU.
89	 */
90  	pgd_t **pgd;
91	pgd = (pgd_t**)&per_cpu(current_pgd, smp_processor_id());
92
93	SUPP_BANK_SEL(1);
94	SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
95	SUPP_BANK_SEL(2);
96	SUPP_REG_WR(RW_MM_TLB_PGD, pgd);
97
98	set_cpu_online(0, true);
99	cpu_set(0, phys_cpu_present_map);
100	set_cpu_possible(0, true);
101}
102
103void __init smp_cpus_done(unsigned int max_cpus)
104{
105}
106
107/* Bring one cpu online.*/
108static int __init
109smp_boot_one_cpu(int cpuid)
110{
111	unsigned timeout;
112	struct task_struct *idle;
113	cpumask_t cpu_mask = CPU_MASK_NONE;
114
115	idle = fork_idle(cpuid);
116	if (IS_ERR(idle))
117		panic("SMP: fork failed for CPU:%d", cpuid);
118
119	task_thread_info(idle)->cpu = cpuid;
120
121	/* Information to the CPU that is about to boot */
122	smp_init_current_idle_thread = task_thread_info(idle);
123	cpu_now_booting = cpuid;
124
125	/* Kick it */
126	cpu_set(cpuid, cpu_online_map);
127	cpu_set(cpuid, cpu_mask);
128	send_ipi(IPI_BOOT, 0, cpu_mask);
129	cpu_clear(cpuid, cpu_online_map);
130
131	/* Wait for CPU to come online */
132	for (timeout = 0; timeout < 10000; timeout++) {
133		if(cpu_online(cpuid)) {
134			cpu_now_booting = 0;
135			smp_init_current_idle_thread = NULL;
136			return 0; /* CPU online */
137		}
138		udelay(100);
139		barrier();
140	}
141
142	put_task_struct(idle);
143	idle = NULL;
144
145	printk(KERN_CRIT "SMP: CPU:%d is stuck.\n", cpuid);
146	return -1;
147}
148
149/* Secondary CPUs starts using C here. Here we need to setup CPU
150 * specific stuff such as the local timer and the MMU. */
151void __init smp_callin(void)
152{
153	extern void cpu_idle(void);
154
155	int cpu = cpu_now_booting;
156	reg_intr_vect_rw_mask vect_mask = {0};
157
158	/* Initialise the idle task for this CPU */
159	atomic_inc(&init_mm.mm_count);
160	current->active_mm = &init_mm;
161
162	/* Set up MMU */
163	cris_mmu_init();
164	__flush_tlb_all();
165
166	/* Setup local timer. */
167	cris_timer_init();
168
169	/* Enable IRQ and idle */
170	REG_WR(intr_vect, irq_regs[cpu], rw_mask, vect_mask);
171	crisv32_unmask_irq(IPI_INTR_VECT);
172	crisv32_unmask_irq(TIMER0_INTR_VECT);
173	preempt_disable();
174	notify_cpu_starting(cpu);
175	local_irq_enable();
176
177	cpu_set(cpu, cpu_online_map);
178	cpu_idle();
179}
180
181/* Stop execution on this CPU.*/
182void stop_this_cpu(void* dummy)
183{
184	local_irq_disable();
185	asm volatile("halt");
186}
187
188/* Other calls */
189void smp_send_stop(void)
190{
191	smp_call_function(stop_this_cpu, NULL, 0);
192}
193
194int setup_profiling_timer(unsigned int multiplier)
195{
196	return -EINVAL;
197}
198
199
200/* cache_decay_ticks is used by the scheduler to decide if a process
201 * is "hot" on one CPU. A higher value means a higher penalty to move
202 * a process to another CPU. Our cache is rather small so we report
203 * 1 tick.
204 */
205unsigned long cache_decay_ticks = 1;
206
207int __cpuinit __cpu_up(unsigned int cpu)
208{
209	smp_boot_one_cpu(cpu);
210	return cpu_online(cpu) ? 0 : -ENOSYS;
211}
212
213void smp_send_reschedule(int cpu)
214{
215	cpumask_t cpu_mask = CPU_MASK_NONE;
216	cpu_set(cpu, cpu_mask);
217	send_ipi(IPI_SCHEDULE, 0, cpu_mask);
218}
219
220/* TLB flushing
221 *
222 * Flush needs to be done on the local CPU and on any other CPU that
223 * may have the same mapping. The mm->cpu_vm_mask is used to keep track
224 * of which CPUs that a specific process has been executed on.
225 */
226void flush_tlb_common(struct mm_struct* mm, struct vm_area_struct* vma, unsigned long addr)
227{
228	unsigned long flags;
229	cpumask_t cpu_mask;
230
231	spin_lock_irqsave(&tlbstate_lock, flags);
232	cpu_mask = (mm == FLUSH_ALL ? cpu_all_mask : *mm_cpumask(mm));
233	cpu_clear(smp_processor_id(), cpu_mask);
234	flush_mm = mm;
235	flush_vma = vma;
236	flush_addr = addr;
237	send_ipi(IPI_FLUSH_TLB, 1, cpu_mask);
238	spin_unlock_irqrestore(&tlbstate_lock, flags);
239}
240
241void flush_tlb_all(void)
242{
243	__flush_tlb_all();
244	flush_tlb_common(FLUSH_ALL, FLUSH_ALL, 0);
245}
246
247void flush_tlb_mm(struct mm_struct *mm)
248{
249	__flush_tlb_mm(mm);
250	flush_tlb_common(mm, FLUSH_ALL, 0);
251	/* No more mappings in other CPUs */
252	cpumask_clear(mm_cpumask(mm));
253	cpumask_set_cpu(smp_processor_id(), mm_cpumask(mm));
254}
255
256void flush_tlb_page(struct vm_area_struct *vma,
257			   unsigned long addr)
258{
259	__flush_tlb_page(vma, addr);
260	flush_tlb_common(vma->vm_mm, vma, addr);
261}
262
263/* Inter processor interrupts
264 *
265 * The IPIs are used for:
266 *   * Force a schedule on a CPU
267 *   * FLush TLB on other CPUs
268 *   * Call a function on other CPUs
269 */
270
271int send_ipi(int vector, int wait, cpumask_t cpu_mask)
272{
273	int i = 0;
274	reg_intr_vect_rw_ipi ipi = REG_RD(intr_vect, irq_regs[i], rw_ipi);
275	int ret = 0;
276
277	/* Calculate CPUs to send to. */
278	cpus_and(cpu_mask, cpu_mask, cpu_online_map);
279
280	/* Send the IPI. */
281	for_each_cpu_mask(i, cpu_mask)
282	{
283		ipi.vector |= vector;
284		REG_WR(intr_vect, irq_regs[i], rw_ipi, ipi);
285	}
286
287	/* Wait for IPI to finish on other CPUS */
288	if (wait) {
289		for_each_cpu_mask(i, cpu_mask) {
290                        int j;
291                        for (j = 0 ; j < 1000; j++) {
292				ipi = REG_RD(intr_vect, irq_regs[i], rw_ipi);
293				if (!ipi.vector)
294					break;
295				udelay(100);
296			}
297
298			/* Timeout? */
299			if (ipi.vector) {
300				printk("SMP call timeout from %d to %d\n", smp_processor_id(), i);
301				ret = -ETIMEDOUT;
302				dump_stack();
303			}
304		}
305	}
306	return ret;
307}
308
309/*
310 * You must not call this function with disabled interrupts or from a
311 * hardware interrupt handler or from a bottom half handler.
312 */
313int smp_call_function(void (*func)(void *info), void *info, int wait)
314{
315	cpumask_t cpu_mask = CPU_MASK_ALL;
316	struct call_data_struct data;
317	int ret;
318
319	cpu_clear(smp_processor_id(), cpu_mask);
320
321	WARN_ON(irqs_disabled());
322
323	data.func = func;
324	data.info = info;
325	data.wait = wait;
326
327	spin_lock(&call_lock);
328	call_data = &data;
329	ret = send_ipi(IPI_CALL, wait, cpu_mask);
330	spin_unlock(&call_lock);
331
332	return ret;
333}
334
335irqreturn_t crisv32_ipi_interrupt(int irq, void *dev_id)
336{
337	void (*func) (void *info) = call_data->func;
338	void *info = call_data->info;
339	reg_intr_vect_rw_ipi ipi;
340
341	ipi = REG_RD(intr_vect, irq_regs[smp_processor_id()], rw_ipi);
342
343	if (ipi.vector & IPI_CALL) {
344	         func(info);
345	}
346	if (ipi.vector & IPI_FLUSH_TLB) {
347		     if (flush_mm == FLUSH_ALL)
348			 __flush_tlb_all();
349		     else if (flush_vma == FLUSH_ALL)
350			__flush_tlb_mm(flush_mm);
351		     else
352			__flush_tlb_page(flush_vma, flush_addr);
353	}
354
355	ipi.vector = 0;
356	REG_WR(intr_vect, irq_regs[smp_processor_id()], rw_ipi, ipi);
357
358	return IRQ_HANDLED;
359}
360